Guetzli, Google’s New JPEG Encoder

Last week, Google released to open source JPEG encoder that can create images file sizes 35% smaller than currently available methods. Called Guetzli, which means cookie in Swiss German, it seems new possibilities for the format that’s been around since the late 1980s!

Using a different method than other optimizers, Guetzli doesn’t have a set of rules or laws in a race to the lowest file size when encoding images.

Instead, Guetzli relies on a tool that measures differences between images the way the human eye detects differences called butteraugli.